A thin film array panel is provided, which includes: a plurality of signal lines including contact parts for contact with an external device; a plurality of thin film transistors connected to the signal lines; an insulating layer formed on the signal lines and the thin film transistors; and a plurality of pixel electrodes formed on the insulating layer and connected to the thin film transistors, wherein the insulating layer includes a contact portion disposed on the contact parts of the signal lines and having a thickness smaller than other portions and the contact portion of the insulating layer includes an inclined portion having an inclination angle smaller than about 45 degrees.